1. Field of the Invention
The present invention relates to a composition for use in the treatment of tumors and the immunization of organisms against tumors.
2. Description of the Related Art
It has been established very recently by various scientific teams that the localized injection, into organisms with a tumour, of synergistic tumour cells producing an interleukin could result in the rejection of this tumour by the organism.
This was demonstrated for Interleukin-2 by Bubenik et al. (Immunology Letters 19, 279-282, 1988; Immunology Letters, 23, 287-292, 1989) and confirmed in particular by Fearon et al. (Cell., 60, 397-403, 1990) and by Ley et al., (European Journal of Immunology 1991, 21: 851-854; Res. Immunol., 1990, 141: 855-863).
The authors of these articles mention that rejection is accompanied by memorization of the response. The animal is therefore vaccinated against subsequent development of the same type of tumour even if the latter is grafted onto a different site.
Synergistic cancer cells producing Interleukin-4 have also been tested with similar results, as reported by Golumbek (Science, 254,713-716,1991) and Tepper et al. (Cell, 57, 503-512, 1989) and also cells producing the tumour necrosis factor (TNF) as described by Blankenstein et al. (J.Exp.Med., 173,1047-1052, 1991).
The possibility has also been put forward (Pardoll, Current Opinion in oncology, Vol.4, N.degree.6, 1124-1129, 1992) of co-introducing into tumour cells derived from the organism to be treated both cytokine encoding genes and suicide genes such as the thymidine-kinase gene of the herpes virus (HSVTK).
The author mentions that this strategy is particularly complicated and requires 100% cell transduction.
This strategy was nevertheless tested in Application N.degree. 92/05262 PCT/US 91/06 612 made by THE JOHN HOPKINS UNIVERSITY and THE UNIVERSITY OF TEXAS SYSTEM which related to compositions intended to potentialize the immune response to a tumour, comprising cells derived from this tumour:
which express an immunopotentializing polypeptide, and PA1 have a gene likely to destroy these cells, or a suicide gene. PA1 cells, viruses or bacteria transiently expressing in the organism at least one gene enabling them to produce in vivo one or more immunomodulators, and PA1 viruses, or cells producing viruses, said viruses if possible preferably infecting dividing cells of the treated organisms and carrying within their genome at least one gene whose expression in the dividing cells will cause their destruction.
The immunopotentializing polypeptide may be a cytokine such as interleukin 1 or 2. The suicide gene may, for example, be the thymidine-kinase gene.
The cell compositions that are the subject of this Application are derived from the organism to be treated and are therefore synergistic for this organism. They do not comprise a virus.
The systems described in these publications contain disadvantages for their application in man.
In all these publications the cells producing interleukin are cells from the individual or from a synergistic individual, which are modified to express interleukin.
For the treatment of humans, one disadvantage of this method is the risk that the cells expressing interleukin injected into the organism might continue to develop even after rejection of the tumour.
To remedy this drawback a method of treatment was tested which consists of injecting into the organisms allogeneic or xenogeneic cells expressing genes enabling them to produce in vivo one or more biologically active substances, such as Interleukin-2 (cf. patent application FR 91 14 119 dated Nov. 15, 1991 entitled: "Cell composition for the treatment of human or animal organisms").
This method permits the transient treatment of the organism with these substances as the cells, on account of their immunological nature, are rejected by the organism.
This treatment was tested by injection in the vicinity of the tumour cells (LPB tumour) of Interleukin-2 producing allogeneic cells 9 days after inoculation with the tumour cells. A beneficial effect was observed in the form of diminished tumour growth over several days.
This is a transient effect and, under the conditions used, does not always cause induction of immunity memorization specific to the inoculated tumour cell. In animals treated in this way subsequent inoculation of the same tumour cell (Lewis tumour) can lead to tumour growth.
Moreover the effect observed, that is to say diminished tumour growth, is not always sufficient to cause elimination in the entire tumourous mass.
It will be noted that, in all the experiments described in the state of the art the absence of tumourous growth is generally measured on a healthy animals, and very rarely on pre-established tumors. GOLUMBEK et al.((1991) Science, 254, 713-716) and PORGADOR et al. ((1992) Cancer Res. 52; 3679-3686), for example, injected a composition in both these cases for the purpose of treating a pre-established tumour, but at the time of treatment the pre-established tumour was neither visible nor macroscopically detectable.
With a different approach TROJAN et al.,((1992) Proc. Natl. Acad. Sci., USA, B9, 4874-4878, (1993) Science, 259, 94-97) modified the immunogenicity of a tumour in the rat (glioma) by transfecting the tumour cells with a vector coding for a complementary DNA antisense to IGF 1 (Insulin-like Growth Factor 1). The authors mention that the injection of these modified cells results in the absence of tumorigenicity and in a remote effect on a pre-established tumour. Nevertheless this approach is restricted to tumour cells secreting IGF as autocrine growth factor and it requires the manipulation of each tumour cell to generate a specific immunity response.
Another proposal based on the infection of tumour cells with a retrovirus carrying the gene encoding the thymidine kinase of herpes was tested on two models. In the first model Culver et al. ((1992) Science, 256, 1550-1552) developed a therapeutic approach in which a rat glioma (brain tumour) is injected with xenogeneic cells producing a retroviral vector into which was inserted the gene coding for the herpes thymidine kinase. After local production of TK.sup.+ viral particles, which will infect the rapid growth cells (tumour cells), systemic treatment with Ganciclovir (Merck Index, reference 4262), induces massive regression of the pre-established tumourous mass. However this type of treatment is not fully effective since, in the described experiment, complete macroscopic and microscopic tumourous regression was observed in only eleven animals out of the fourteen treated. Also, a small number of tumour cells (4.times.10.sup.4 cells) are injected and treatment (injection of fibroblast cells producing TK.sup.+ viral particles) is carried out at a very early stage (from Day 5 onwards) after inoculation of the tumour cells. The major disadvantage nevertheless remains the non-observance in this model of immunity memory vis-a-vis secondary inoculation of the same tumour cells.
The second model develops a relatively similar approach to that mentioned above. Established macroscopic, hepatic tumours are treated by intratumourous injection of xenogeneic fibroblasts producing viral particles expressing the TK gene of the herpes virus and selectively infecting the tumour cells. After a period of transduction of the TK gene in the tumour cells in vivo, most of the tumourous mass is eliminated by treatment with Ganciclovir (GVC). However, the major disadvantages remain the same, namely the absence of any guarantee regarding the full elimination of tumour cells and memorization.
Both these approaches have recourse to xenogeneic cells capable of expressing viral particles able to transduce the TK gene in the tumour cells. The second approach, compared with that developed by Culver et al., is more effective as it mimics a situation of hepatic metastases of primary colon cancer and it is applied to a well developed tumourous site that is macroscopically visible.
Under another technique described in Application N.degree. 93/02556 PCT/US 92/06 188 (UNIVERSITY OF ROCHESTER) cancer patients are reinjected with their own cancer cells into which a suicide gene was introduced.
The tests described in this latter application show that treatment with this type of transgenic cell composition then with the substance relative to the suicide gene, can bring about the destruction in the organism not only of the cells that are the subject of the application but also of other cancer cells. The destruction of transgenic cells in the organism also brings about the destruction of other non-transgenic cancer cells. The compositions described in this application do not comprise any virus.
Finally, a technique based on the combined use of electric impulses and local injections of allogeneic or xenogeneic cells secreting Interleukin-2 has recently been developed (MIR et al., (1992) Compte-Rendu de L'Academie des Sciences de Paris, serie III, 314, 539-544).
According to MIR et al. (Eur.J.Cancer 1991, 27, 68-72), electrochimiotherapy consists of locally injecting bleomycine and applying electric impulses in the vicinity of the tumour.
The combined use of these two methods potentialises the anti-tumourous effect observed in each of the two methods used singly.
However, electrochimiotherapy has the major disadvantage, even in combined use with cells secreting Interleukin-2, of being easily applied only in tumours with at least one accessible site.
It therefore arises clearly from the state of the art analysed above that the methods described are not always effective, particularly against established tumours, and that they do not systematically provide immunity memory specific to that tumour or only permit the local treatment of tumours.